1. Field of the Invention
The present invention relates to a controller. Further, the present invention relates to a touch panel including the controller and an electronic device including the touch panel in a panel portion.
2. Description of the Related Art
In recent years, a technique by which power consumption of a touch panel is reduced (a technique for reducing power consumption) has been developed.
As an example of the technique for reducing power consumption, a technique by which the touch panel is turned off or automatically brought into a low-power consumption driving state when the touch panel is not in use has been known.
For example, Patent Document 1 discloses a technique by which a touch panel is turned off in the case where a touch input is not performed for a certain period of time. In Patent Document 1, a touch-event detector which detects a touch input is provided, whereby after the touch panel is turned off, the touch panel can be activated on the basis of a detection result in the touch-event detector.